On Tue, Nov 06, 2012 at 09:42:22PM +0800, howard chen wrote:
I am going to use post_action for mirroring the load for performance
testing to new backend.
But according to the doc:
Note: this directive “has subtleties” according to Maxim D., so use
at your own risk.
There is no official documentation on the “post_action” directive
(you may check yourself at http://nginx.org/en/docs/), and it’s on
purpose. What you are quoting is wiki.
- Is the post_action blocking to the user request? Or the sub request is
truly async and not affecting to the user?
The post_action is executed in the context of the main request,
and will block further work on the same client connection till
That is, it’s unlikely a good idea to use post_action for
performance testing. I would recommend logging requests instead
and re-executing them with a separate process.